#include<stm32f4xx.h>
#define K1_PIN                GPIO_Pin_4                  
#define K1_PORT               GPIOE                   
#define K1_CLK                RCC_AHB1Periph_GPIOE             

#define K2_PIN                GPIO_Pin_3                     
#define K2_PORT               GPIOE                             
#define K2_CLK                RCC_AHB1Periph_GPIOE           

#define K3_PIN                GPIO_Pin_14                    
#define K3_PORT               GPIOB                      
#define K3_CLK                RCC_AHB1Periph_GPIOB       

#define K4_PIN                GPIO_Pin_15                       
#define K4_PORT               GPIOB                           
#define K4_CLK                RCC_AHB1Periph_GPIOB                     

#define K1_PREESED            0x01                            
#define K2_PREESED            0x02                       
#define K3_PREESED            0x04                            
#define K4_PREESED            0x08           

void key_event(unsigned int* STEMP_angle);